Current Orbit Tank Mount, Adjustable Arm Bracket Kit  Part# 4193
Fits most rimless and framed aquarium up to 1" think with a depth of 14 inches
 
Kit includes
Adjustable Aluminum Arm, 10" adjustable slide / move light fixture front to back 
Adjustable Tank mount bracket, 3 preset vertical height adjustables (vertical fixture height)
Qty (2)  Fixture mounting clips
Arm  Dimensions 2.5" W x 7.5" H x 15" L
 
Sizing Recommendations
 
Orbit IC,  Orbit Marine, Satellite Plus, Satellite Plus Pro
Light Lengths  18", 24", & 36"  - requires 1 Arm Mount
Light Lengths  48",  72"   -    requires 2 Arm Mounts 
 
Single Orbit,  Marine PRO
Light Lengths 18", 24"  - Requires 1 Arm Mount
Light Lengths  36", 48" - Requires 2 Arm Mounts
Light Lengths 72" - Requires 3 Arm Mounts
 
Dual Orbit, Marine Pro
2 x 24"  - Requires 2 Arm Mounts
2 x 48" - Requires 3 Arm Mounts
2 x 72"  - Requires 4 Arm Mounts